Throwoff mechanism for printing presses



1940- w. K. ECKHARD THROWOFF MECHANISM FOR PRINTING PRESSES Filed 00;. 21, 195i; 4 Sheets-Sheet 1 INVENTOR ATTORNEYS Oct. 1, 1940. w, K, ECKHARD 2,216,565

'THROWOFF MEGHANISM FOR PRINTING PRESSES Filed Oct. 21, 1958 Y 4 Sheets-Sheet 2 INVENTOR ATTORNEYS Oct- 1. 1940- w. K. ECKHARD I THROWOFF MECHANISM FOR PRINTING PHESSES Filed Oct. 21, 1938 4 Sheets-Sheet 3 INVENTOR ATTORN EYS Oct. 1, 1940. w. K. ECKHARD THHOWOFF MECHANISM FOR PRINTING PREsSES Filed Oct. 21, 1938 4 Sheets-Sheet 4 R 4 o T M m w v m n r E n Y /MB 8 a w "16 m 0.3 n in. I Mm a 0 W M w w n W a 1 a m w M I P a I m n m w r P M M n M WM a w M 0 .0 Z P m mi 0 z 6 a m M EM a mu e M m 6 M K r m a 0 f N. EH T 962'! 7" g ATTORNEYS Patented Oct. 1, 1940 UNITED STATES PATENT OFFICE THROWOFF MECHANISM FOR PRINTING PRESSES William K. Eckhard, Westerly. R. L, assignor to O. B. Cottrell & Sons Company, Westerly, R. 1.,

8 Claims.

The object of my invention is to provide a novel sheet controlled fluid pressure operated throwofi mechanism for sheet feed rotary printing presses.

My invention includes fluid pressure means automatically operated by the feeding or nonfeeding of the sheets for throwing a form cylinder on'or off impression. My invention also includes said means for throwing a plurality of form cylinders successively on or off impression.

My invention also includes fluid pressure operated diaphragms acting on both sides of each end of each form cylinder box for automatically moving the form cylinders successively into or out of printing contact with their impression cylinder; said diaphragms serving to eliminate pistons and piston packings and also leakage of the actuating fluid, and to permit much lower pressures and greater pressure areas on the form cylinder boxes than where pressure fluid actuated pistons are used, as well as occupying less space. This arrangement permits an individual adjustment of the actuating pressure for each side of each form cylinder box according to the location of the form cylinder with respect to the impression cylinder. This arrangement also permits extreme accuracy in the pressure exerted by each form cylinder upon its impression cylinder at each side of said form cylinder, this being especially desirable where heavy printing forms are located at one side and light printing forms at the other side of the form cylinder.

My invention also includes mechanically operated valves for controlling the passage of the liquid pressure to and from the diaphragms.

My invention also includes, more particularly, a ball trip setting mechanism for controlling the movements of the valves.

A practical embodiment of my invention is represented in the accompanying drawings.

Fig. 1 represents in side elevation, partly in section, so much of a five color sheet feed rotary printing press as embodies my improved throwofi mechanism, the first and second form cylinders being shown thrown off impression, and the third, fourth, and fifth form cylinders being shown thrown on impression.

Fig. 2 represents a detail side view, partly in section, of the sheet controlled trip setting mechanism for operating the slide valves to control the movements of the form cylinders through the liquid pressure diaphragms.

Fig. 3 represents a similar view of a portion of the impression cylinder cam and its adjacent parts.

Fig. 4 represents, on a larger scale, .a portion of the ball trip setting mechanism and its operating cam with the parts in one inoperative position when the sheets are being properly fed through the press.

Fig. 5 represents a similar view with the parts in another of their inoperative positions.

Fig. 6 represents a similar view with the parts in one of their operative positions when a sheet has not been fed properly into the press.

Fig. '7 represents a similar view with the parts in another of their operative positions.

Fig. 8 represents, on a still larger scale, a detail longitudinalqsection through one of the mechanically operated liquid pressure controlling l5 slide valves and its adjacent parts.

Fig. 9 represents a detail side view of one of the form cylinder boxes and the liquid pressure operated diaphragms for moving it, together with their adjacent parts.

Fig. 10 represents a detail view of the sheet detector mechanism which controls the operation of the ball trip setting mechanism.

Fig. 11 represents a timing diagram showing the relative positions of the detector, feed cylin- 25 der and trip setting mechanism.

The impression cylinder is denoted by l and its shaft by 2.- Each of the form cylinders is denoted by 3 and its shaft by 4. Each form cylinder shaft 4 is journaled at each end thereof 30 in a box 5. Each form cylinder box 5 slides in a slot 6 radially toward and away from the impression cylinder I. The sheet feed cylinder is denoted by 1, the sheet transfer cylinder 8, and the usual swinging detector by 9.

Liquid pressure operated diaphragms l0 and H, such as the well known Linderman diaphragms, are located against the inner and outer sides respectively of each form cylinder box 5, which diaphragms are connected by pipe lines 40 I2 and I3 to the chamber Id of a mechanically operated slide valve l5 of the piston type. This slide valve is provided with two heads l6 and H. The chamber M of the slide valve is connected to a pump l8 through a pipe line I9. This chamber 5 I4 is also connected through a pipe line 20 to a tank M which supplies the liquid to the pump l8 and which receives the returning liquid through the said pipe line 20. The slide valve heads l6 and I! are arranged in the proper positions within the chamber l4 so that as they are moved back and forth they will admit the liquid pressure to and release it from the diaphragms Ill and H.

The movement of each slide valve I5 is automatically controlled by the feeding or non-feeding of a sheet to the press to operate through the diaphragms l0 and H for throwing the form cylinders successively on or of? impression. The mechanism which I have shown for accomplishing this result is as follows:

The detector 9, located in the path of the incoming sheets, is of any well known or approved form. In the present instance this detector is shown as being pivoted on one arm 22 of a rock lever, the other arm 23 of which is arranged to contact with one arm 24 of a rock lever, the other arm 25 of which is connected by a rod 26 to one arm 21 of a cam operated lever, another arm 28 of which being provided with a stud or roller 29 which contacts with the face of a rotary cam 3|] fast on the shaft 3| of the sheet feed cylinder 1. This last named lever has a third arm 32 provided with a camshoe 33 which is arranged in position to contact with a stud or roller 34 carried by a pawl 35 pivoted on one arm 36 of a second cam lever, the other arm 31 of which carries a stud or roller 38 which contacts with the face of a rotary cam 39 fast on the said feed cylinder shaft 3|. abutment 4| arranged in position to be engaged by and disengaged from the pawl 35. This lever 40 is connected by a rod 42 to one arm 43 of a rock lever, the other arm 44 of which carries a rod 45 which slides vertically in the bore 46 of a member 41 of the ball trip setting mechanism. A rod 49 is fitted to slide in a cross bore 49 of the member 41. A plunger 50 is slidable in the member 41, which plunger is connected to one arm 5| of a cam lever, the other arm 52 of which carries a stud or roller 53 which contacts with a rotary cam 54 fast on the shaft 55 of the sheet transfer cylinder 8. A ball 56 is free to be moved along within the bores 46 and 49, which ball is controlled by the movements of the rods 45, 48 and 58, as will hereinafter appear. The rod 48 has a bore 51 for receiving the free end of the plunger 56 when the ball 56 is located in the bore 46 below the cross bore 49. This rod 48 is connected to one arm 58 of a rock lever, the other arm 59 of which is connected by a rod 60 to one arm 6| of a toggle lever, the other arm 62 being connected by a link 63 to a swinging cam 64 for throwing a switch 65 in one direction by contact with the stud 66, carried by said switch. The lever arm 6| is connected by a rod 61 to one arm 68 of another toggle lever, the other arm 69 of which being connected by a link 10 to a swinging cam 1| for engaging the stud 66 to throw the switch 65 in the opposite direction. These cams 64 and 10 and the switch 65 are carried by a rotary disc 12 fast on the impression cylinder shaft 2, which disc has inner and outer concentric grooves 13 and 14, in either one of which grooves, according to the position of the switch 65, travels the stud or roller 15, carried by one arm 16 of a rock lever, the other arm 11 of which is connected to the slide valve |5 for moving the slide valve to control the liquid pressure of the diaphragms lo and II to throw the form cylinder off or on impression.

In the present instance I have shown three of these switches 65, carried by the impression cylinder disc 12.

The upper arm of the swing detector 9 is arranged to be swung out of locking engagement with a latch 18, by the proper feeding-in of a sheet along its support 19, into engagement with the said detector. Stops and 8| limit the swinging movements of the latch 18.

It will be understood that a single slide val e A rock lever 40 has a tooth or controls the flow of pressure liquid to and from the diaphragms at both ends of each form cylinder, 2. cross pipe 82 connecting the pipe lines I2 and a cross pipe 83 connecting the pipe lines l3.

A spring 84 acting on the lever arm 22 yieldingly holds the lever arm 23 against the adjustable stop 85. A spring 86 on the rod 45 yieldingly holds the rod in its lowered position with the ball 56 out of the path of the plunger 58. A spring 81 yieldingly holds the toggle levers which operate the cam 64 and 1| in their broken positions.

In operation, when the sheets are being properly presented in register, the detector 9 is swung to the full line position shown in Fig. l0. Under these conditions the parts controlled by the cams 30, 39 and 54 operate normally, the ball 56 of the trip setting mechanism remaining in its inoperative position out of the path of the plunger 50. The switches 65 of the disc 12 are also held in their position, to cause the rollers 15 of the slide valve operating levers 16, 11 to travel along the inner groove 13 and thus cause the liquid pressure operated diaphragms II to hold the form cylinders on impression.

When a sheet fails to be properly presented the detector 9 will occupy the dotted position shown in Fig. ID, in its locked engagement with the latch 18. This will hold the lever arms 23, 24 and 25, 28, raised, thereby preventing the cam roll 29 from falling on the face of its cam 38. This also stops the movement of the lever arm 32 and its cam 33, thereby preventing the cam 33 from releasing the pawl 35 from its engagement with the abutment 4| of the lever 40. This permits the cam 39 through the roll 38 and arm 31 to rock the lever 4|], whose rod 42 thereby rocks the lever 43, 44. This raises the ball 56 into the path of the plunger 50 of the cam lever 5|, 52, whose roller 53 travels on the face of the cam 54. This cam 54 rotates the plunger 50 through the ball 56, and arm 48 rocks the levers 58 and 59 to throw the switches 65 into position to cause the rollers 15 of the slide valve operating lever 16, 11 to successively move out into the outer concentric groove 14 of the disc 12 to successively move the slide valve |5 for causing the liquid pressure to move the diaphragms ID to throw the form cylinders controlled thereby oiT impression.

It will be understood that as soon as a sheet is properly presented, the dectector 9 will be moved to cause the parts to return to their normal positions and the slide valves to operate for automatically and successively throwing the form cylinders back on impression.

It is evident that various changes may be resorted to in the construction, form and arrangement of the several parts without departing from the spirit and scope of my invention, and hence I do not intend to be limited to the particular embodiment herein shown and described, but

What I claim is:

1. In a throwoff mechanism for sheet feed rotary printing presses, an impression cylinder, a plurality of form cylinders and means operated by the presence or absence of a properly fed sheet for automatically and successively throwing the form cylinders on or off impression, said means including fluid pressure operated diaphragms acting on the form cylinders and mechanically operated valves for controlling the operation of the diaphragms.

2. In a throwoff mechanism for sheet feed rotary printing presses, an impression cylinder,

a plurality of form cylinders, means operated by the presence or absence of a properly fed sheet for automatically and successively throwing the form cylinders on or off impression, said means including fluid pressure operated diaphragms acting on the form cylinders, slide valves for controlling the fluid pressure, rock levers, a rotary disc and a switch carried thereby for rocking said levers to operate the slide valves.

3. In a throwofi mechanism for sheet feed rotary printing presses, a sheet operated detector, an impression cylinder, a plurality of form cylin ders, their boxes, fluid pressure operated diaphragms on both sides of said boxes, slide valves for controlling the operation of the diaphragms and means under the control of the detector for moving the slide valves to cause the diaphragms to automatically and successively throw the form cylinders on or off impression.

4. In a throwofl. mechanism for sheet feed rotary printing presses, a sheet operated detector, an impression cylinder, a plurality of form cylinders, their boxes, fluid pressure operated diaphragms on both sides of said boxes, slide valves for controlling the operation of the diaphragms and means under the control of the detector for moving the slide valves to cause the diaphragms to automatically and successively throw the form cylinders on or ofi impression, said means including valve operating rock levers, a rotary disc and a switch carried thereby for controlling the movement of the levers.

5. In a throwofi mechanism for sheet feed rotary printing presses, a sheet operated detector, an impression cylinder, a plurality of form cylinders, their boxes, fluid pressure operated diaphragms on both sides of said boxes, slide valves for controlling the operation of the diaphragms and means under the control of the detector for moving the slide valves to cause the diaphragms to automatically and successively throw the form cylinders on or ofi impression, said means including valve operating rock levers, a rotary disc, a switch carried thereby for controlling the movement of the levers and a ball trip setting mechanism for controlling the movement of the switch.

6, In a throwofi mechanism for sheet feed rotary printing presses, a sheet operated detector, an impression cylinder, a plurality of form cylinders, their boxes, fluid pressure operated diaphragms on both sides of said boxes, slide valves for controlling the operation of the diaphragms and means under the control of the detector for moving the slide valves to cause the diaphragms to automatically and successively throw the form cylinders on or ofi impression, said means including valve operating rock levers, a rotary disc having inner and outer concentric grooves and a switch for throwing the levers successively into the inner or outer groove.

7. In a throwofi mechanism for sheet feed rotary printing presses, a sheet operated detector,

an impression cylinder, a plurality of form cylinders, their boxes, fluid pressure operated diaphragms on both sides of said boxes, slide valves for controlling the operation of the diaphragms and means under the control of the detector for moving the slideyalves to cause the diaphragms to automatically and successively throw the form cylinders on or off impression, said means including valve operating rock levers, a rotary disc having inner and outer concentric grooves, a switch for throwing the levers successively into the inner or outer groove and a ball trip setting mechanism for controlling the movement of the switch.

8. In a throwoff mechanism for sheet feed rotary printing presses, a sheet operated detector, an impression cylinder, a plurality of form cylinders, their boxes, fluid pressure operated diaphragms on opposite sides of said boxes, slide valves for controlling the operation of the diaphragms, a rotary disc having inner and outer annular grooves, slide valve operating levers having groove engaging studs or rollers and a switch controlled by the detector for automatically causing the studs or rollers to travel in either of said grooves according to the presence or absence of a properly fed sheet.

WILLIAMK. ECKHARD. 

